DEVELOPMENT OF ENERGY IN THE LOWER FUNGI. 541 



energy, and the products of tissue change and the 

 excreta. Among the latter the isolated ferments and 

 the ptomaines require a more detailed consideration. 

 Closely allied to these we have those two peculiar, and 

 for hygienic purposes important, phases of the vital 

 activity -of the fungi, viz., the fermentative activity and 

 the development of disease. 



1. Review of the Tissue Change and Development of 

 Energy in the Lower Fungi. 



For the development of those movements and 

 alterations of material particles, which make up the 

 life of the vegetable cell, a certain amount of energy 

 must in the first place be set free ; without this these 

 movements, and therewith the life of the plant, would 

 cease. A small fraction of the necessary energy is 

 obtained by osmosis; by far the greatest portion is, 

 however, supplied to the plant by the splitting up of 

 complex chemical compounds, and by regrouping of 

 the atoms in more stable compounds, in other words 

 by similar transformations to those which occur in the 

 animal body, and which then give rise to the energy 

 which is necessary for the various functions of the 

 animal economy. The vital processes in vegetables Tissue change 

 and animals differ only in the fact that the compounds 

 to be broken up are taken up by the animal bodies in j 

 an unaltered condition, while in the case of vegetables plants, 

 they must first be built up from more simple materials by 

 means of the chlorophyll apparatus ; in the lowest forms 

 of plants, viz., in the fungi, however, this preparative 

 apparatus is absent, and the materials are taken up in 

 the form of relatively complex molecules. What, how- 

 ever, is absolutely necessary, and common to the life 

 of the cells of animals, vegetables, and fungi, is the 

 decomposition of complex organic compounds accom- 

 panied with the liberation of energy. 



These decompositions are carried out by means of the Decomposi- 

 living protoplasm. The latter can apparently, like a 



